Response of an Antarctic Peninsula fjord to summer katabatic wind events

TitleResponse of an Antarctic Peninsula fjord to summer katabatic wind events
Publication TypeJournal Article
Year of Publication2019
AuthorsLundesgaard O., Powell B., Merrifield M., Hahn-Woernle L., Winsor P.
Volume49
Pagination1485-1502
Date Published2019/06
Type of ArticleArticle
ISBN Number0022-3670
Accession NumberWOS:000469352500002
Keywordsantarctica; Atlantic water; bays; Downslope winds; driven; dynamics; glacier; greenland; gulfs; ice shelves; models; ocean; oceanography; seas; stratified inlet; subglacial discharge; surface-layer; tide model; wind stress
Abstract

Fjords along the western Antarctic Peninsula are episodically exposed to strong winds flowing down marine-terminating glaciers and out over the ocean. These wind events could potentially be an important mechanism for the ventilation of fjord waters. A strong wind event was observed in Andvord Bay in December 2015, and was associated with significant increases in upper-ocean salinity. We examine the dynamical impacts of such wind events during the ice-free summer season using a numerical model. Passive tracers are used to identify water mass pathways and quantify exchange with the outer ocean. Upwelling and outflow in the model fjord generate an average salinity increase of 0.3 in the upper ocean during the event, similar to observations from Andvord Bay. Down-fjord wind events are a highly efficient mechanism for flushing out the upper fjord waters, but have little net impact on deep waters in the inner fjord. As such, summer episodic wind events likely have a large effect on fjord phytoplankton dynamics and export of glacially modified upper waters, but are an unlikely mechanism for the replenishment of deep basin waters and oceanic heat transport toward inner-fjord glaciers.

DOI10.1175/jpo-d-18-0119.1
Student Publication: 
No